acetyl-l-carnitine huberman Carnitine Supplementing With Acetyl-L-Carnitine Increases Fat

Burg D, Filippov DV, Hermanns R, van der Marel GA, van Boom JH, Mulder GJ

Health Psychol Res

Manufacturer expiration dates vs reality What expiration dates mean: Conservative estimate of guaranteed potency Usually based on accelerated stability testing Designed to ensure 90-100% potency through date Regulatory and liability considerations Why stated dates are conservative: Expensive to test long-term (years) Manufacturers want safety margin Better to underestimate than overestimate Varies by company (research chemicals vs pharma) Research peptide "expiration": Often no formal expiration date COA (Certificate of Analysis) shows testing date General rule: 2 years from COA date if frozen 6-12 months from COA if refrigerated Real-world peptide longevity: Frozen peptides often remain 80%+ potent at 3-5 years Refrigerated peptides good 12-18+ months if properly stored Much depends on storage conditions and handling When to trust peptides past "expiration": Stored frozen continuously: Very likely still good Stored refrigerated: Probably good if within 1-2 years Room temp storage: Don't trust past weeks Visual inspection passes (see below) COA relatively recent (within 2-3 years) When to discard despite date: Visible discoloration or changes Exposed to heat or temperature extremes Stored at room temperature for extended period Seal broken (contamination risk) Smell or visual contamination Shelf life after reconstitution (liquid peptides) Reconstituted peptides have much shorter lifespans

World Urbanization Prospects: The 2018 Revision (United Nations, 2018)